羊栖菜多糖的结构与免疫活性关系的研究

Hizikiz fusiformis, an edible brown algae with high medicinal and nutritional value is widely distributed along the coastlines of China. The polysaccharides of H. fusiformis have exhibited diverse biological properties, including anti-tumor, antihyperlipidemia, and immunomodulating activities. Little is known, however, about the relationship between structure and activities of these polysaccharides. This project will rely on the Zhejiang Dongtou breeding base, extract and purify homogeneous polysaccharides such as fucoidin, alginate and laminaran, analyze their structural features by enzymolysis, chemical methods and instrumental analysis, and prepare oligosaccharide fragments with clear structure by enzyme or acid hydrolysis. The immunomodulative activities of these polysaccharides and oligosaccharides on a variety of immunocyte will be studied in mouse, using enzyme-linked immunosorbent assay and flow cytometry. The structural basis and pathway of immune activities of polysaccharides and oligosaccharides from H. fusiformis will be analyzed based on these studies. The results of this project will provide high quality materials and direction for the study on structural modification and molecular mechanism of polysaccharides. All these would lay the theoretical foundation for the development of food and drug from H. fusiformis and provide important scientific support for sustainable development for the H. fusiformis industry in China.

羊栖菜具有较高的药用和食用价值，在我国沿海分布广泛，多糖是羊栖菜的重要活性成分之一。目前已经发现羊栖菜多糖具有抗肿瘤、调节免疫、降血脂等多种活性，但其结构和作用机理并不明确。本项研究将依托于浙江洞头羊栖菜养殖基地，从羊栖菜中提取纯化出均一的褐藻糖胶、褐藻胶和褐藻淀粉；应用化学方法和现代仪器分析手段研究羊栖菜多糖的结构特征；通过酶解和酸水解，制备结构特征清晰的寡糖片段；用羊栖菜多糖和寡糖免疫小鼠，应用ELISA和流式细胞术等技术测定羊栖菜多糖和寡糖片段对多种免疫细胞等的影响；进而分析羊栖菜多糖发挥免疫活性的结构基础和作用途径。为后续羊栖菜多糖的结构修饰和活性作用的分子机制研究提供优质的样品支持和方向性指导，为海藻多糖免疫作用机理的深入探讨做出贡献，同时为羊栖菜食品与药品开发奠定理论基础。这些工作将为我国羊栖菜产业的可持续发展提供重要的科技支撑。

羊栖菜具有较高的药用和食用价值，在我国沿海分布广泛，多糖是羊栖菜的重要活性成分之一。目前已经发现羊栖菜多糖具有抗肿瘤、调节免疫、降血脂等多种活性，但其结构和作用机理并不明确。本项研究将依托于浙江洞头羊栖菜养殖基地，从羊栖菜中提取分离出冷提羊栖菜多糖SFCP，热提褐藻糖胶SFPF、水溶性褐藻胶SFWA和碱溶性褐藻胶SFAA，并从SFPF中纯化出三个均一级份SFPF-1、SFPF-2和SFPF-3；应用化学方法和现代仪器分析手段研究了其中SFPF-2的结构特征，表明它是一种主链1-3链接的岩藻聚糖，在C-2，C-3或C-4具有硫酸根取代基；用羊栖菜多糖免疫小鼠，证明其具有良好的免疫刺激活性，直接作用于离体小鼠免疫细胞和单核巨噬细胞白血病细胞系RAW264.7也证明其免疫刺激活性，羊栖菜多糖能够抑制LPS引起的极性炎症反应，并具有良好的清除羟自由基和DPPH的活性，细胞水平上也证明了羊栖菜多糖能够预防细胞受到的氧化损伤，同时推测羊栖菜多糖的免疫调节活性与NF-κB信号通路和Nrf2细胞通路相关，本研究为后续羊栖菜多糖的结构修饰和活性作用的分子机制研究提供优质的样品支持和方向性指导，为海藻多糖免疫作用机理的深入探讨做出贡献，同时为羊栖菜食品与药品开发奠定理论基础。这些工作将为我国羊栖菜产业的可持续发展提供重要的科技支撑。